The issue of these discussions is not actually the balance, but the versatility of the characters. I get the feeling the Chaze was intended for a full rogue one squad with their kits in mind. GK was intended to help Jedi, and DN was intended for a full sith team with him as the leader.
However, because the developer does nothing to limit their abilities to the factions they are intended for, you get this Tank/Support and no DPS meta which is super lame to fight against and honestly, pretty stale.